Air suspension is very delicate. If, after the vehicle has been stationary for about 12 hours, the height on one side of the vehicle drops more than 1.5 cm when measured from the wheel arch to the tire, we will determine that there is a slight air leak in the air spring or distribution valve on that side and warn you of the high subsequent repair costs.

We use two steps: 1. Insert a medical-grade endoscope through the spark plug hole to visually inspect cylinder wall scratches and carbon buildup on the piston top; 2. Extract an engine oil sample to check for large metal debris or emulsification (caused by coolant leakage).

The registration certificate will show whether the previous owner was an individual (registered with ID) or a company (registered with a business license). Vehicles under a company may be driven by multiple people, so we will focus on checking the uniformity of interior wear and the condition of the chassis.